The invention relates to a system for marking a region within an image of a road map detail displayed on a vehicle video screen. Such systems are used in vehicle navigation systems. The navigation system automatically computes the optimal driving route for the respective location of the vehicle based on knowledge of the destination and, by way of corresponding visual and/or acoustic indications, provides assistance to the driver for driving to the destination without the use of conventional map material. The marking of a region causes the navigation system to drive around that region.
In this context, it is known from U.S. Pat. No. 6,542,812 to mark the region by use of a suitable drawing device so that the drive takes place around the marked outlines. It is easy to recognize that such a system is not particularly suitable for use in comfort-optimized vehicles.
Furthermore, a correction possibility can be provided only very inconveniently, if at all. In this case, a correction is also a change of the displayed map detail with respect to its size as well as also with respect to its position.
Required long periods of looking at the system and for operating the system are also a disadvantage associated with the known system.
It is an object of the invention to provide a system of the above-mentioned type, by which a marking of a region within a road map detail displayed on a vehicle video screen becomes possible in an easy and rapid manner.
According to the invention, a system is provided for marking a region within an image of a road map detail displayed on a vehicle video screen, characterized in that a location of the region can first be selected by a control element. The region can be constantly fixed by way of an enter function. The region represents one of several administrative levels, and the administrative level and, thereby, the size of the region can be changed by a rotating movement of the control element, which can be rotated about a longitudinal axis.
The enter function fixes the selected region. As a result of the movement of the control element, the size of the region is changed corresponding to the administrative levels controlling this region. An administrative level is the sequence of administrative units. In Germany, this is, for example, the succession of the nation, the land, the administrative district of the land, the county, the town, and the part of town. As a result of the enter function, the uppermost and the lowermost or the last authoritative administrative level is selected.
Advantageous embodiments of the invention are described herein. These embodiments relate to the possibility of changing the dimensions and/or the position of the region by use of the control element, to fixing an implemented selection, and to the manner of how this fixing can be carried out by use of the control element and can be included in the navigation system.
Finally, the inventive system provides a solution in the event that the vehicle is already situated within the marked region. In this case, the navigation system suggests a route by which the vehicle leaves this region as quickly as possible.